Robust secure UAV relay-assisted cognitive communications with resource allocation and cooperative jamming

This paper considers a novel scenario, where physical layer security issue is studied in unmanned aerial vehicles (UAVs)-assisted cognitive relay system. A secondary vehicle (SUAV) delivers information from multiple Internet of things (IoT) devices to user (SU) under the spectrum sharing with primary users (PUs). In processing transmission SUAV relay, eavesdropper (SE) wiretaps transmitted by UAV imperfect location information. order confuse SE, friendly jammer employed transmit jamming signals SE. To prevent SE wiretapping as much possible, we aim maximize average worst-case secrecy rate network jointly optimizing robust trajectories and power power, trajectories, causality interference temperature (IT) threshold constraints. Thus, formulate original problem which challenging non-convex problem. We propose an effective algorithm solve attain locally optimal solution based on successive convex approximation (SCA) technology alternate optimization method. Simulations are offered demonstrate that our proposed resource allocation scheme can effectively improve performance comparison other benchmark schemes.